Crude oil production from subterranean reservoirs can include three distinct recovery phases: primary recovery, secondary recovery, and tertiary recovery. During primary recovery, the natural pressure within the reservoir can drive the oil to the production wellbore where pumps or other artificial lift devices can deliver it to the surface. During secondary recovery, water or gas can be injected into the reservoir to further drive or “push” the oil into the production wellbore. During tertiary recovery, chemicals, gas and/or heat can be injected into the reservoir to change the interfacial properties and physical properties of the heavy crude oil trapped in the pores of the reservoir rock, to further enhance recovery.
Tertiary recovery continues to present technical and economic challenges for producers, due in part to the relatively high viscosity of the trapped oil. Improvements in this field of technology are therefore desired.